1. Field of Invention
The present invention relates to a process for preparing activated polyether polyols having a low viscosity and a good reactivity which are particularly suitable for resin transfer molding systems.
2. Brief Description of the Prior Art
Polyethers polyols and process for preparing and using the same are known in the art. Of particular interest here are internally catalyzed polyether polyols which offer a faster reactivity towards isocyanates than ordinary hydroxyl group-containing materials but slower reactivity than ordinary amine group-containing materials. These activated polyether polyols are useful in resin transfer molding systems. As would be realized, there is an ongoing research into the preparation of polyethers, which have desirably fast reactivity and processability at the same time.
U.S. Pat. No. 3,654,370 discloses amine-terminated polyethers which are prepared by reacting polyols with ammonia under catalyzed high temperature reaction conditions.
U.S. Pat. No. 4,902,768 discloses N-(polyoxyalkyl)-N-(alkyl)amine by catalytic amination of an appropriate polyol by reacting the polyol with a primary or secondary amine in the presence of a catalyst such as nickel.
U.S. Pat. No. 5,015,774 discloses a process for preparing polyoxyalkylene polyamines having secondary amino groups at the end of the polyamine by reacting a polyoxyalkylene polyol with a primary amine in the presence of a catalyst containing nickel and zinc, cobalt and zinc or, zinc and nickel.
By the present invention, there is provided an efficacious method of preparing activated polyethers polyols which by virtue of the activation are very well suited to use in RIM systems.